Prosthetic device



Dec. 8, 1959 M. M. BAaR PRosTx-mrc DEVICE Filed nec. 24. 195s v ATmR/VEY United States Patent() 2,915,760 PRosrHE'TIC DEVICE Milford M. Bair, Amity Harbor, N.

Application December 24, 1956, Serial No. 630,236

15 Claims. (Cl. 3'-2) This invention relates to articial limbs or prosthesis for leg amputees and to the method of supporting the weight of such amputees.

It is the desideratum of this invention to provide more useful and practical means and methods for supporting the weight of a leg amputee, whether the amputee be double or single, by attempting to approach, as closely as possible, the support that is normally afforded by the natural limbs cooperating with the pelvic girdle.

It has been the accepted practice to secure the artificial limb or prosthesis about the wearers thighs, socketing the stumps in the prosthesis to transmit the body weight from the thighs to the prosthesis. To accomplish this, straps secured about the thighs, are the immediate means whereby the weight is transmitted from the body to the articial limb. From actual experience, it is known that the strap srtuctures being rigid and cumbersome in nature, are extremely uncomfortable after any period of prolonged use. The wearer experiences an annoying constriction and tightening about his thigh because of the weight that is transmitted to the straps thereat. Hence if the iit of the strap is not precise, there results a rubbing unhealthful irritation in those areas of movement of the strap relative to the thigh. This is even more true with double amputees who are forced to wear two such prosthesis, thereby doubling the strain and uncomfortable experience. y

In carrying out the purposes and objects of this invention, namely to achieve a support that approaches the function performed by normal limbs, it is within the concept of the invention that the prosthesis be positioned about areas of the anatomy, as close as possible to the location of the natural limbs to provide the desired results.

To understand the invention, it is first important to know the principles of support afforded by the normal limbs in their connection with the pelvic girdle. The pelvic girdle defines surfaces for the attachments of the trunk and lower limbs. Its most important mechanical function, however, is to transmit the weight of the trunk and upper limbs to the lower extremities or lower limbs; that is to say, the pelvic girdle is the jointure or bridge between the lower limb supports and the remaining upper,

body portion. Hence, one of the chief functions of the pelvic girdle is that of transmitting the body weight to the lower limb supports. For the reception and the diffusion of the Weight, the pelvic girdle is provided with two acetabulum cavities, each of which is generally strengthened lby two additional bars running toward the pelvis and ischium. The ischium forms the lower and back part of the hipbone while the acetabular cavities each form a socket for the receipt of the hip of the supporting femur.

Amputation or loss of the natural support afforded by the lower limbs, removes the means to which the pelvic girdle normally transmits the body weight to the ground during walking and standing positions. In carrying out the objects of the invention, advantage is seized upon the natural formation of the pelvic girdle and its included Figs. l and 2 wherein the wearer thereof is in a reclining 2,915,760 s Patented Dec.l 8,

2 structure. The rest or seat conveniently positioned beneath the pelvic girdle and retained in position therebeneath, serves to absorb the body weight from the pelvic girdle substantially in the same manner as does the head of the femur socketed in the acetabular cavity. The rest or seat is then supported in such manner that the weight transmitted thereto is, inturn, transmitted thereby directly to the ground in substantially the same manner and location relative to the pelvic girdle as do the natura limbs.

It will be readily recognized that the most nearly perfect structure would be one whereby the pelvic girdle is supported directly at the acetabulum. However, inaslmuch as we are here concerned with amputees who have had only a portion of their limb or limbs removed, such support directly at the acetabulum is not feasible.v In practical application it has been found that the portion of the pelvic girdle most easily adapted for support is the ischium although it will be clear that other portions thereof may also be applicable, depending upon 'the particular bone structure and nature of the amputation.

Hence it is another object of the invention to take advantage of the formation of the pelvic girdle by providing a rest or seat therefor at the ischium, as close to the acetabular cavity as possible, and onto which the weight of the body may rest; thence retaining the seat and its position and supporting it above the ground in the nature and in the location relative to the pelvic girdle substantially as does a natural limb. p

Heretofore the wearer of an artificial limb has lacked the ability to pivot the same at the heel thereof in the same manner and with the same degreeV of rotation as a natural leg. In order to simulate a pivoting motion, the amputee was forced to undulyk swing his body in the attempt and the hope that by such exaggerated manipulation, he could cause the rigid artificial limb to assume a shuiiiing sliding arcuate motion about the ground. y

Accordingly, it is another object and feature of the invention to enable the amputee to actually rotate or pivot his prosthesis at the heel thereof about the ground in substantially the same manner and with substantially the same degree of rotation as one would pivot his natural foot without contorted or excessive swinging motion of the thigh or upper body regions. 4

Other and further objects of my invention reside in the structures and arrangements hereinafter more fully described with reference to the accompanying drawings in which: I

Fig. 1 is a rear view of the seat or reference member Ain its sitting position anda partial View of the support structure therefor constructed in accordance .with the teaching of the invention.

Fig. 2 is a side view of the reference member shown in Fig. 1 in its resting position.

Fig. 3 is a side view of the reference member shown in position.

Fig. 4 is a top view of the reference member and part of the supporting structure therefor.

Fig. 5 is a front view of the wearers legs with the strap secured thereabout.

Fig. 6 is a rear view of the Wearers leg showing the rreference memebr retained thereto.

Fig. 7 is an enlarged view of the foot swivel.

Referring now to gures of the drawing, numeral 10 generally identifies the upper section of the prosthesis. The prosthesis comprises at least a seat member 12. For the most ecient and effective support of the pelvic girdle, the seat member 12 is positioned proximate, or as close as possible, to the joint of the femur with the acetabulum. In this position the seat memberl affords` a resting surface for the lowermost pre-,selected portion of the pelvic girdle. For purposes of explanation and to provide a better understanding of the invention, although many predetermined areas of the pelvic girdle may be utilized, the ischium will be referred to hereinafter as the pre-,selected portion for the sake of clarity.

The-seat 12 includes a resting surface 14 that is adapted to take the weight from the ischium lof the pelvic girdle when positioned therebeneath. Member 12 is of suf- .cient area as to extend beneath the rbottommost portion of the ischium to support the weight of the body during lthe walking and standing movements of the wearer. At its forward or leading edge 16, it is curved inwardly, ythe depth of the curve and the configuration .thereof being determined by the curvature of the thigh of the wearer.

To determine the shape of the curve 16 and also that of the resulting lobes or leaves 18, it is recommended that .a mold be taken of the thigh at the portion thereof proximate the joint of the femur with the acetabulum, the Vmold thus serving to provide a guide from which the curve 16 and the lobes or leaves 1S may be formed. The leaves 18 thence serve to encompass slight portions of the thigh. Once again, in order that the seating surface 14 be made comfortable, it may be contoured, as seen in Figs. 2 and 3, by taking a mold of that portion of the body directly beneath the ischium. However, in practice a number of members 12 each having a different shape and size, may be applied to the wearer until the ,most comfortable one is found.

The care with which the surface 14, the curve 16 and leaves 13 are formed will result in a more comfortable prosthesis, eliminating the incidence of irritation. The edges of the seat 12 are smoothed, as shown in Figs. l to 3 to eliminate rough edges, thereby removing possible sharp surfaces that might penetrate or irritate the adjacent skin areas.

Because the seat 12 carries the weight rested upon it by the pelvic girdle, it is retained and supported in position beneath the weight-transmitting pre-selected ischium at all times. It is necessary to retain this position at all times regardless of the movements ofthe wearer. Hence, for the purpose of providing a clearer insight to the concepts of the invention, the seat 12 is also referred to as a reference member. It is so termed because it retains substantially the same fixed reference plane, whether the wearer is standing or walking as depicted in Fig. A2, or is sitting in a partial or a full reclining position as seen in Fig. 3.

When the wearer is in the standing or walking position (Fig. 2) the pre-selected ischium `is located directly above the surface 14. This surface, being smoothly kcontoured exactly to that of the body contour of the wearer, forms therewith a cooperating mating working engagement. When the wearer is in a reclining position, as shown in Fig. 3, the surface 14 remains in its vreference plane, but the 4pelvic girdle has changed its position relative thereto. During the transition movement of the wearer from a reclining position to a standing or walking position, the pelvic girdle is caused to assume two different positions; the first one wherein the lsame is out of engagement with the surface 14, and the second position wherein the same is in mating working engagement therewith. Inasmuch as surface 14 is substantially fixed in its reference plane, it is positioned always to accept and cooperate with the pre-selected ischium as the isctlliinn moves into mating contour engagement therew1 To enable the member 12 to transmit the Weight applied thereto to the `ground in the manner yof a natural limb, `the prosthesis of the Vinvention comprises a vframework supporting structure that simulates the wearers .natural limb. The upper portion of theprosthesis includes a pair of spaced rigid frames Ztl and '22. The one frame 20 extends upwardly along the `outermost side of the wearers thigh to provide lateral or s'idewise supi port for the body. It is retained close against the thigh by a form-fitting strap 24 to which it is made integral.

The frame 22, spaced from the first frame 20, also extends upwardly along a portion of the wearers thigh but on the side thereof opposite that of the frame 20. Frame 22 is bent slightly inward toward the seat member 12 to support the same as directly as possible. The topmost portion of the frame 22 is made integral with a rigid strap 26 which is co-extensive with the form-fitting strap 24 and formed as an integral part thereof. The rigid strap 26 thus defines an extension of the form-fitting strap 24 and, on its other side, denes an extension of a semi-iiexible strap 28. The semi-flexible strap 28 is secured at its end adjacent .to the strap 26 to the frame 22.

As seen in Fig. 5, the form-fitting and flexible straps 24 and 28 are joined together or made integral to form a complete strap structure. In order that the completed strap structure defined by the form-fitting strap portion 24, the rigid strap portion 26, and the semi-flexible strap portion 28 may be secured to and about the thigh, there is provided at the Vfront thereof a suitable fastening adjustor 39. For simplicity of explanation, the adjuster 3i) is here shown in the form ,of a lacing structure.

The form-fitting strap portion 24 cooperates with the outermost sideway portion of the thigh to take the weight therefrom and distribute it on to the framework structure defined by the frames 20 and 22. The semi-flexible strap 23 and the adjustor 30 permits proper and comfortable placement of the completed strap structure about the thigh of the wearer. The rigid strap portion 26, being retained in position at its one end by its connection to the frame 22 and, at its other end, by the form-tting strap portion 24, is sutliciently stable to support the seat member 12 in its desired position.

As will be recognized, because it is desirable to retain the seat 12 in its reference plane during the movements of the pelvic girdle relative thereto, the same must be connected with the support structure therebeneath, namely, frames 20 and 22 and the retaining strap 24, 26 and 28 in such manner that it will be permitted ,movement relative thereto. The strap structure serves to retain the seat 12 in its pre-determined position beneath the pre-Selected ischium, whereas the supporting framework 20, 22 transmits the weight from the seat and strap structure to the ground.

In Order ,that the weight may be transmitted efficiently and effectively, the supporting structure, including the strap and the framework, is positioned about the thigh to assume the same location as the femur relative to the acetabulum and simulate the natural limb of the wearer.

Hence, it will be clear that the transmission of the wearers weight from the seat to the strap and thence to the frame, and finally to the ground, Vis done so along substantially the same aligned position relative to the pelvic girdle as would the wearers natural limb.

Mounted to the under-side of the seat 12 is a supporting operable tripod. The tripod comprises a pair of arms 32 and 34. Each arm is substantially the saine in construction and manner of operation and connection between the `rigid strap 26 and the under-side lof the seat 12. The top of the arm 34 is formed as a hall joint 36 that ts within and 'is secured to the under-side of the seat 12 by Va ball joint receiving socket 38 secured to the seat at its plate 40. Arm '32 Yis formed substantially L shaped; its leg 42 extending through an eyelet opening defined in a strap connector element The eyelet of the connector 44 is of sufficient internal diameter as to swingably receive the leg 42 therein.

The leg 42 is retained in the eyelet and an adjustment relative vtherein by the provision of a nut 46 adjustably threaded along the end thereof. 1n order that the arm 32 Vhave substantially universal connection with the rigid strap 26, the eyelet connector element 44 is pivotally mounted to the strap 26 at 48. The -pivotal mounting 48 thus permits'the eyelet and the arm 32 to pivot about ythe "As noted previously, arm 34 is connected in exactly the same manner between the seat 12 and the outer surface outer surface of the strap 26, while the leg 42 may swing within its connector 44. of the rigid strap portion 26 as arm 32. That is to say, arm 34 is secured at its balled head 50 thereof to the under-side of the member 12 by a cooperating receiving socket 52 secured thereto at its plate 54. The L shaped leg 56 of the arm 34 is swingably mounted in a slightly enlarged opening of an eyelet of strap type connector element 57 which, in turn, is pivotally mounted at 58 to the outer surface of the rigid strap portion 26. Adjustment of the arm 34 relative to the eyelet 57 may be accomplished by the rotation of the threaded nut 60.

Because of the normal formation of the thigh, the rigid strap 26 slopes downwardly slightly from its jointure with the form-fitting strap portion 24 toward the arm 22 and the semi-exiblestrap portion 28. However, in some instances, the strap need not slope, depending upon the bone structure of the wearer. In order that the seat 12 may be retained substantially level, the arm 32 connected to the rigid strap 26, is made longer than the arm 34. lThe result is that its respective lobe 18 is thereby thrust well beneath the ischium and toward the inside of the thigh.

Completing the tripod arrangement of support, is a vretractable plunger structure generally identified as 62.

The tripod structure 62 comprises a tubular housing 64 which is secured at a slight angle to the vertical intermediate its ends by a suitable securing means 66 to the outer surface of the rigid strap 26. An additional support for the plunger structure 62 is provided by a further suitable securing means 68 that joins the lower portion of the tubular housing with the supporting frame 22. The securing means 66 and 68 serve to retain the retractable plunger structure in a substantially fixed position.

Slideably mounted for movement within the tubular `housing 64, is a threaded plunger 70 having formed, at

its upper end, a ball joint 72. The plunger 70 is connected between the supporting framework and the underside of the seat 12 by a ball joint receiving socket 74 that is in turn, fastened to the seat 12 at its attendant plate 76. The ball joint connection 72, 74 thus permits pivotal movement of the seat relative to the plunger.

Rotatably mounted on the threads of the plunger 70 is an adjustment member or nut 78. The threaded position of the adjustment member 78 along the plunger 70 serves to control the depth to which the plunger will be permitted to retract into its tubular housing 64, the member 78 thereby serving as a stop seat cooperable with the end of the housing. As the description proceeds, it will also be realized that by adjustment of the member 78 along the threaded plunger 70, the reference plane of the seat member 12 may be varied to a position that is most comfortable for the wearer.

The tripod structure thus described, and as seen in Figs. l-4 and 6, provide a suitable operable support whereby the weight applied to the surface 14 of the seat member 12 may be transmitted directly to the supporting structure, including the thigh strap and framework 20 and 22, which form a diagrammatic part of the artificial limb or prosthesis simulating the natural limb of the wearer.

In actual use, the seat member 12 is positioned as close as possible to the joint of the femur with the acetabular cavity. In this position the leaves 18 surround adjacent portions of the thigh while the `cavity 16 accommodates or receives the bony portion of the femur. The seat 12 is thus accurately positioned beneath the pre-selected portion or ischium of the pelvic girdle.

Seat member 12 is retained in this position by the thigh strap structure 24, 26, 28. The strap thus retains in position not only the seat 12 beneath the pre-selected ischium and proximate the joint of the femur with the acetabulum,

but also holds the supporting simulatednatural limb Pb" frames 20 and 22 in alignment with that positionwhich the wearers natural limb normally assumes. The reference plane of the seat is then adjustedby rotation of the adjustment member 78 along the plunger 70 to provide complete contact and comfortable mating engage ment with the pre-selected ischium. j

During the standing or walking positions, the skinof the wearer is caused to assume the dot-dash position generally identified by the numeral 80 in Fig. 2. Although the showing in Fig. 2 is slightly exaggerated, it is to be understood that, because the seat 12 is moved in and retained close to femur-acetabulum joint, it depresses the surrounding skin surfaces; hence we see a depressed skin surface 82. In this regard, it will be noted that the skin surface 82 beneath the seat 12 does not actually come into contact with the rigid strap portion 26 but is generally slightly spaced therefrom. However, the skin in the area of the hipbone and rectum sits smoothly and comfortably on the surface 14 and smoothly curves upwardly away therefrom as seen at 84. The slight depression at 82 is in the fleshy area of the body and creates no discomfort.

During the walking movements of the wearer, the tripod structure pivots at the upper ball joints thereof relative to the seat 12 and in movement with the strap structure fastened about the thigh. The level of the reference plane of the seat is maintained by the adjusted plunger 70 resting at 78 on the top of the housing 64. The slight pivotal movement of seat 12 that occurs at the ball joint 72, 74 of the plunger structure 62 does not affect the position of the seat member 12 when the wearer leans sideways during the walking movements but rather serves to retain and support it in itsrefe-rence plane. The pivotal connections of the spaced tripod arms 32, 34 with both the under-side of the seat 12 and with the rigid strap portion 26, also serve to maintain the position of the seat member relative to the pre-selected ischium, thereby providing a constant supporting weight-receiving surface. Additional support is provided by arm 34 resting on strap 2 6 as at 27.

The transition movement of the wearer from the standing or walking position to the reclining position, as shown in Fig. 3, is unhampered. As the thigh of the weareris bent relative to the pelvic girdle, the strap 24,26, 28 is caused to move therewith. During this movement, the arms 32 and 34 and the plunger 70 pivot relative to the under-side of the seat. As the thigh is extended outwardly, the distance between the strap and the seat member increases. This increased distance is facilitated and permitted by the movement of the plunger 70, out from the housing 64 to an extended position therefrom as will be seen in Fig. 3. The arms 32 and 34 of the tripod structure merely pivot relative to the seat and swing about their connection with the rigid strap 26 at both their respective connectors 44, 57 and the mountings 48, 58 of such connectors with the strap 26 During this reclining movement the longer length of arm 32 swivels and tilts the seat 1-2 slightly away from the center of the body and pelvic girdle to a comfortable position beneath the wearers buttocks. f

During the wearers transition movement from thereclining position to the standing position, the seat 12 retains its reference plane; the thigh of the wearer moving downwardly causes the strap secured thereabout, to move closer in distance to the under-side of the seat. There is a consequent pivoting and swinging of the tripodarms 32, 34 between the rigid strap portions 26 and the seat 12 to the position previously described. Simultaneously therewith, the plunger 70 retracts into its housing 64 and abuts the same at 78 when the wearer is in his normal standing position.

In order that the wearer of the prosthesis be permitted v to pivot his foot about the ground in a manner simulating the natural pivoting action, there is secured to the same, a swivel structure generally identified by the numeral 86,

'which define stop surfaces.

It comprises a substantially cylindrical housing 88 through which the amputated stump of the wearer is permitted to extend. Cylinder 88 is secured to the upper portion of the artificial limb or prosthesis by any suitable means as indicated at 90. Secured to the cylinder S, or formed as a part thereof, is an annular projection 92 that rotates smoothly within a cooperating annular chamber '94. Chamber 94 is defined by the combination of an L-shaped cup lmember 96 and a ring 98 that are secured or made integral with each other and form a part of the lower portion liti() of the prosthesis or artificial limb. lncluded in the lower portion i@ is an engaging sock 161 into which the amputated limb may be securely socketed. This sock may be of any well known construction that will serve to receive the lower end of the amputated limb and secure it to the lower portion lili? for conjoint rotation. Hence when the lower end of the amputated limb is moved in rotation, it causes the sock 101 and portion i0@ to rotate with it.

In operation, when the amputated limb that is socketed in the lower portion ltli) of the prosthesis is rotated, the socket 101 within which it is securely seated and also the framework Mt), is caused to rotate therewith. This rotation permits the foot or lower portion of the prosthesis at the lowermost end (not shown) of the framework 109 to rotate relatively to the upper portion thereof as identified for the purposes of explanation, by the framework 20, 22 (Fig. 7).

However, in order to overcome the possibility that the pivoting of the limb at the foot thereof about the ground will assume unnatural proportions or appearancesfor example, persons with amputations have a tendency to over-exaggerate their movements, thereby possibly resulting in a greater arc or pivoting movement of the heel of the foot of the instant inventionthere is provided a rotative lost-motion connection 1502. This connection is 'fitted between the substantially fixed upper framework Ztl, 22 of the prosthesis and the pivotable lower framework 100.

Defined in the cylindrical member 88 of the upper framework is at least one aperture 163. The aperture M33 is in the nature of a slot having side walls lltli and 106 Cooperating stop members 08 and 11@ are adjustably mounted about the interior peripheral surface of the ring 98 (said adjustment is not shown in the drawings). By fine adjustment of the spacing of the stops i493 and lit) relative to their cooperating stops 106 and 164 respectively, there will be permitted limited movement 0f the lower portion of the prosthesis relative to the upper portion, thereby eliminating the possibility of excessive abnormal rotation.

Hence when the amputee desires to pivot his artificial limb at the foot thereof, it will be unnecessary for him to lpivot the whole of his body but merely to move the end of his amputated limb that is socketed in the frarner work 10i?. It will be readily recognized that this arrangement of structure thereby permits the wearer to pivot his foot but obviates the necessity of the wearer to swing or excessively manipulate the upper regions of his body or even the pelvic girdle.

While there have been shown and described and pointed out the fundamental novel features of the invention yas applied to a lpreferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and -in its operation may be made by those skilled in theart, without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.

I claim:

l. An artificial limb comprising a seat to be positioned beneath a lpreselected portion of the body of the wearer `to support thejweight thereof, support means spaced from lsaid seat, said support means including means to secure the seat to the thigh of the wearer, means retractably movable between said securing means and seat to connect the same in spaced relationship and being retractable vto permit relative movement of the seat and the securing means during movements of the thigh of the wearer `to retain the seat fixed in position beneath said preselected body portion and to transmit the weight vfrom said -seat to the securing means.

2. An artificial limb comprising a reference member adapted to define a seat having a fixed reference position on which the pelvic girdle of the wearer may rest, retractable means movably connected to said reference member to retractably move to retain the same in its fixed reference position to seat the pelvic girdle, and means spaced from said reference member and cooperable with said last named means to retain said member fixed to -the thigh of the wearer.

3. An articial limb comprising a member for seating a pre-determined portion of the pelvic girdle, support means connected with said member to support the same in seating position beneath said pre-determined portion, said support means including means adjustable about and movable with the thigh of the wearer, and means -to retractably and movably connect said member to `said adjustable means during the movements of the wearer.

4. In an articial limb, a member adapted to be posi'- tioned in a fixed reference plane beneath the ischium of the wearer to provide a support therefor, means adapted to be secured about the thigh of the wearer and for movement therewith relative to said member, and means operatively connecting said last named means spaced from said member and for said relative movement, said operative connecting means having means to vary the space between said securing means and member to retain said member in its fixed reference plane.

5. An artificial limb construction comprising a member to be pre-determinedly positioned beneath the ischium to support the weight of the wearer when in the standing and walking positions, limb support means extending from a surface upon which the wearer may stand and walk and cooperating with said member to support the same above the surface, said means including means securable about the thigh of the wearer for movement therewith, and means movably operable to variably space said securable means and member from each other to retain the latter in position beneath the ischium to support the weight of the wearer during the standing and walking movements.

6. ln an artificial limb that is adapted to take the place of a normal limb by supporting a pre-selected surface of the pelvic girdle proximate the connection of the femur with the acetabulum, a member on which the pre-selected surface of the pelvic girdle may rest, said member being of sufiicient area to extend beneath and support the pre-selected surface and having a reference plane substantially fixed beneath said surface during the standing and walking movements of the wearer, said member being provided with a leading shaped edge to accommodate a portion of the wearers thigh and to enable the same to be positioned proximate the socket connection of the femur with the acetabulum, support means movable relative to said member and cooperable therewith to retain the same beneath said pre-selected surface, and means movably and retractably lmounting said member or said support means to retain its reference plane beneath said pre-selected surface during movements of said support means.

7. in an artificial limb as in claim 6, said pre-selected surface of said pelvic girdle being the ischium thereof.

8. An artificial limb comprising a seat defining a lsurface onto which the weight of the wear-ens body may be transmitted, a support comprising a frame simulating 'the size and shape of the limb 0f the WCrer, said frame being adapted to support said seat above the ground and to transmit the weight of the wearer from said seat to the ground, strap means securable about the thigh of the wearer for movement therewith and connected with said frame, and means movably connecting said seat with said strap means and operable during theA movement of said strap means with the thigh to variably space said strap means and to enable said seat to transmit the weight of the wearers body therefrom to said strap and said frame to the ground.

9. An artificial limb comprising a seat defining a surface on to which the weight of the wearers body may be transmitted, a support comprising a frame simulating the size and shape of the limb of the wearer, said frame being adapted to support said seat above the ground and to transmit the weight of the wearer from said seat to the ground, strapmeans securable about the thigh of the wearer for movement therewith and connected with said frame, means operable during the movement of said strap means to enable said seat to transmit the weight of the wearers body to the ground, a swivel included in said frame and comprising an upper member secured by said frame for movement with said strap means, a lower member secured to the lower end of said frame simulating the foot of the limb for engagement with the ground, a socket in said lower limb in which the amputated stump of the wearer engages to rotate said lower member and a rotatable lost-motion connection between said upper and lower members.

10. In an artificial limb having a seat upon which the wearer may rest his weight, a support for said seat simulating the size and shape of wearers limb and to which the weight of the wearer may be transmitted by way of said seat, said support comprising strap means adapted to be secured about the wearers thigh, said strap means having a rigid portion to extend about the rear of the wearers thigh, a form-fitting portion co-extensive with one side of said rigid portion to extend about the outer contour of the thigh and a semi-flexible portion co-extensive with said form-fitting portion interconnecting same with the other side of said rigid portion, and means to spacedly connect said seat with said support and to vary the spacing therebetween in accordance with the movements of the wearers thigh.

11. An articial limb comprising a seat upon which the wearer may support his weight, a support structure to which the weight of the wearer may be transmitted from said seat to the ground, said support structure simulating the size and shape of the wearers natural limb, strap means to secure said support structure to the wearers thigh for movement therewith, retractable means connecting said seat with said support structure and strap means, and pivotable means interconnecting said strap means with said seat.

12. In a prosthesis for an amputee, a member having a forward curved edge to enable the same to be positioned beneath the pelvic girdle proximate the connection of the femur with the pelvic girdle, said member having a seating surface positioned in a fixed reference plane on which the weight applied by the pelvic girdle may rest, means to secure said member to the wearer, and retractable support means to retractably support said member spaced from said securing means in said proximate position in said xed reference plane and to vary said spacing during the movements of the wearer.

13. In an artificial limb for an amputee, a swivel, said swivel comprising upper and lower relatively rotatable members, said lower member simulating the foot of the wearer, means to secure said upper member to the thigh of the wear, means in said lower member to secure the same to the wearers amputated stump, and lost-motion connection means between said upper and lower members whereby rotation of the wearers stump will cause said lower member to rotate relative to said upper member.

14. In an artificial limb as in claim 13, said lost-motion connection including engageable stop means on said upper and lower members respectively, said stop means on said respective members being spaced each from the other to permit limited relative movement therebetween.

l5. In an artificial limb that is adapted to take the place of a normal limb by supporting a pre-selected surface of the pelvic girdle proximate the connection of the femur with the acetabulum, a member on which the preselected surface of the pelvic girdle may rest, said member being of suflicient area to extend beneath and support the pre-selected surface and having a reference plane substantially fixed beneath said surface during the standing and walking movements of the wearer, said member being provided with a leading shaped edge to accom modate a portion of the wearers thigh and to enable the same to be positioned proximate the socket connection of the femur with the acetabulum, and support means movable relative to said member and cooperable -therewith to retain the same beneath said pre-selected surface, said support means including means pivotably cooperating with said member to enable the same to retain its reference plane beneath said pre-selected surface during the standing and walking movements of said support means and means extensible to permit the wearer to assume a reclining position.

References Cited in the file of this patent UNITED STATES PATENTS 406,328 Yagn July 2, 1889 577,054 Monaghan Feb. 16, 1897 2,004,487 Dorsch June l1, 1935 2,590,782 Mayack Mar. 25, 1952 2,827,897 Pawlowski Mar. 25, 1958 FOREIGN PATENTS 246,833 Switzerland Jan. 3l, 1947 

